SE439114B - PROCEDURE FOR THE TREATMENT OF FLUID WATER AND SUSPENSIONS - Google Patents

Description

The invention aims to provide a new process of the kind initially indicated, wherein as a filter aid for the dewatering, especially of sludge, a product is used, which mainly consists of biologically-physically active substances, through which at least the particle size and the density of the particles dissolved in the suspension is permanently increased for the subsequent filtration, while on the other hand the viscosity of the suspension is lowered.

The problem according to the invention is solved by a method for treating turbid water and suspensions, in particular municipal, industrial and similar sludges for subsequent dewatering, which is characterized in that the turbid water and the suspension, respectively, are brought into contact with a filter aid consisting of fiber particles of well-decomposed, still biologically active compost with a high water uptake capacity and containing 30 - 50% by weight of water, the fiber particles being considerably larger than the particles in the turbid water and suspension, respectively, and the biologically active compost being applied as a homogeneous, loose layer with a thickness of about 2 - 10 cm thickness on the sieve belt in a sieve belt press and this layer is soaked with the cloudy water and the suspension to be dewatered by spraying with five to ten times the applied layer and then pressure dewatered .

Further features of the invention appear from the subclause. The use of compost as a biologically and / or physically active filter aid has a number of advantages.

Due to the compost applied to the sieve belt, the grain size of the sludge particles is significantly increased during the dosed addition of sludge, since these particles, during liquid uptake by the compost, are simultaneously transferred into their capillaries.

As with a deep filtration, the particles, which are smaller than the pore size of the compost particles, penetrate into the capillaries of the latter and deposit there. The viscosity of the sludge is significantly reduced by the fibrous structure of the compost. In addition, since biological, exothermic conversion processes start immediately with the introduction of clear sludge into a compost layer, the temperature of the sludge increases, which leads to a reduction in the surface tension of the sludge water. Compost remains stable during the mechanical dewatering process. The redemption of the sludge particles observed with chemical flocculants during the subsequent mechanical dewatering or aeration thus no longer occurs. Even industrial sludge, which can be flocked with difficulty or not at all, can be dewatered in the manner according to the invention. By adding compost, neither the digestion process is transferred to the chemical transfer of, for example, ready sludge to compost or the ballast water separated from the sludge. In addition, the carbon content of the filter cake is increased, which in a later biological decomposition, for example by decay, has a positive effect on the carbon / nitrogen ratio. which enables the digestion process already takes place in the process step The addition of such additives "drainage". For the subsequent steps of sludge removal, only filter cake and charcoal carriers must be added to the digestion process, which also has a beneficial effect on the mixing process that always precedes a digestion process.

Through the filter aid compost, both the filter cake and the effluent filtrate are inoculated with microorganisms. The microorganisms transferred over the compost in the filter cake initiate a spontaneous biological decomposition process, ie a rot start. Since a sufficient amount of atmospheric oxygen is present at this stage, this decomposition process has an aerobic character, so that no unpleasant odors are present.

The applied compost thus largely absorbs the gases emanating from the sludge, with unpleasant odors. This proves to be particularly advantageous during intermediate storage or transport of the dewatered sludge material. The microorganisms that enter the filtrate, ie the press or ballast water, together with the compost are usually returned to the biological clarification process and find expression there as well as biological grafting, which has a favorable effect on the clarification process. The filtration improved by the filter aid also significantly reduces the proportion of colloidal particles in the filtrate. 7900077-4 The crude heparin, corresponding to about 425,000 USP units or 42.5 g, was extracted three times with 200 ml of 2 M saline solution each, stirring between each extraction at 60 ° C for 1 hour.

The combined extracts were diluted with water until the solution contained about 0.9 mol / liter of chloride ions. 200 ml of an anion exchanger ("LewatitkB) CA 9249", Bayer AG, West Germany) were added in chloride form and stirred for 1 hour. It was then filtered off with suction and washed with about 200 ml of 0.9 M saline solution. The ion exchanger was then stirred for 5 hours with 2 M brine at 40 ° C and then filtered off with suction and washed with 2 M brine. The elution solution was combined with the washing solution and precipitated with 1.5 times the volume of methanol.

The precipitate was separated by centrifugation and washed first with about 50 ml of water-methanol (1: 1.5 by volume) and then with about 50 ml of methanol and dried. It contains .1 J.198 g Na-heparinate with 195 USP units / mg. 15.5 g of a sodium heparinate obtained in the manner described above with about 200 USP units / mg were dissolved in 200 ml of 2 M saline solution.

The solution was sucked off with a suction bottle and the residue was washed first with 30 ml of 2 M saline solution and then with about 250 ml of completely demineralized water. The combined solutions were then transferred with completely demineralized water to a chloride molar of 0.9. Then, in the manner described above, the purification was repeated with 1 liter of "Lewatite RJCA 9249".

The combined elution and washing solution was further processed as described above. After washing and drying the precipitate, 11.2 g of sodium heparinate were obtained, which showed an activity of 251 USP units / mg.

Example Gel 2 In accordance with the procedure described in GB-B-754 885, 3 liters of brine were acidified with stirring with acetic acid to pH 3.1-3.2 (about 50 ml). After a few hours, decantation was performed and the residue was centrifuged. The precipitate was discarded and the combined solutions were neutralized with sodium hydroxide solution.

The solution was slowly added with stirring with an equal volume of methanol. After 45 minutes, the liquid was decanted from the precipitated salt. The suspension was allowed to stand for several hours and the supernatant was decanted and the residue was centrifuged. Precipitation Ch 10 15808022-6 If it proves necessary by the nature of the sludge to be dewatered, an additional layer of filter aid with a thickness of about 1 to 5 cm can be applied to the layer soaked with the suspension in the manner described, by filter aid is preferably meant compost, the moisture content of which is kept as low as possible. serves, for example, dosing augers.

As dosing devices EMBODIMENT EXAMPLE Municipal ready sludge mixed with 10 to 15% of a natural coal carrier is digested in a closed aeration reactor as described, for example, in German Offenlegungsschrift 2 541070 ° C. The biologically active thus obtained, i.e. abundant with microorganisms, actinomycetes, bacteria, small animals, etc. The compost provided can be used immediately as a filter aid without longer intermediate storage.

Claims (2)

10 15 20 7808822-6 6 EATENTKRAV 1. Process for the treatment of turbid water and suspensions, in particular municipal imhsü fl r u fl1 similar sludge for subsequent dewatering, characterized in that the turbid water or suspension is brought into contact with a filter aid consisting of fiber particles of long degraded yet biologically active compost with high water uptake and containing 30 to 50% by weight of water, the fiber particles being considerably larger than the particles in the turbid water and the suspension, respectively, and the biologically active compost being applied as a homogeneous, loose layer with a thickness of about 2 to 10 cm thickness of the sieve belt in a sieve belt press and this layer is soaked with the turbid water and the suspension, respectively, to be dewatered by spraying with five to ten times the applied layer and then pressure dewatered. 2. A method according to claim 1, characterized in that an additional layer of biologically active compost with a thickness of about 1 to 5 cm 2 is uniformly applied to the layer soaked with the turbid water or suspension.